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Geiger counters, radiation detectors, lets see 'em

You have a flashlight or 20 for 'when the 'stroid hits in Dec 2012' but what about knowing if
there are new beta or gamma emitters in your environment ?

---
I have finally dropped coin on a detector, and was wondering what other peeps are using,
or if other peeps are even considering adding one to the toybox ?

I ordered a GQ GMC-300, which will be all the detector needed if the prevailing winds become
soured with ionizing radiation...also good for rockhounding....

When I get it, I will post up pics. Anyone else ?

It makes total sense to own one, Fukushima disaster is still getting worse not better,
and well yes I am actually worried I may come across recycled metal or
other stuff that might be a lot higher than background radiation, and I'd like to know about it,
so I can decide to make distance, or at least know the radioisotopes are around me.

Re: Geiger counters, radiation detectors, lets see 'em

Yeah, I agree. That's a pretty neat watch. I can just imagine trying to explain to non-geeky civilians that your watch detects gamma radiation and that they should clear out of the area because its alarm just went off...

Re: Geiger counters, radiation detectors, lets see 'em

Originally Posted by Wrend

Yeah, I agree. That's a pretty neat watch. I can just imagine trying to explain to non-geeky civilians that your watch detects gamma radiation and that they should clear out of the area because its alarm just went off...

Re: Geiger counters, radiation detectors, lets see 'em

I see Geiger meters at army navy surplus shops all the time, are they actually still accurate and worth the money?

who knows...with a calibrated source, and a new tube, you can use any old detector,
all it has to do it count CPM. ionizing radiation is ionizing radiation no matter which source

if you are in the nuclear industry then you might want
something else that can be programmed with type of source material to get more accurate Sieverts
or something with a mica window that can read alpha emissions

Re: Geiger counters, radiation detectors, lets see 'em

really ? they supposedly do not emit ionizing radiation outside the glass.

when my GMC 300 comes in, I will put 9 trits right on the tube, and post up the counts per minute vs no trits

I'm not sure if they would be detected or not come to think about it but they do emit radiation of some sort but in such low amounts it is negligible. I had a tritium backlit watch in the 70s (still have it but the backlight doesn't work now) and I was told that if you took about 300 of the tritium modules and smashed them in a phone booth it would be about the same amount of radiation you get out in the sun for about 8 hours.

Re: Geiger counters, radiation detectors, lets see 'em

A tritium watch will not trigger a Geiger counter. We've tried it and nothing happened. That was in 1986 around the time of the Chernobyl disaster. A week or so later a friend stopped by the studio wet from a rainstorm and the meter lit up when her rain gear was scanned. Nothing really dangerous, but WAY above background.

Re: Geiger counters, radiation detectors, lets see 'em

if you want to check the sensitivity of that monitor, buy some bananas
On the side note, I consider the aspect of monitoring radiation an exercise in futility... even if you know its presence, what could you do? Radiation contamination is very seldom regional, it "goes with the wind" per se. Knowing it and not knowing what to do after you know it is probably no better than not knowing.

Re: Geiger counters, radiation detectors, lets see 'em

OK, not so fast !
---
I am finding with the unit closed, I cannot detect any additional ionizing radiation from trits

But if I open the unit and put the trits right up to the tube, it increases. In the pics below
I have nothing, a piece of paper with 9 loose trits and CPM goes up, then paper only.

I let each mode sit for a while before the pics. So, trits are weak, but not zero emissions.

(I also laid additional 22mm trits plus the 9 loose ones on there and the CPM went steadily above 100 !)

Nothing different with one loose trit under the tube (little white vertical dash on lower left)9 loose trits
Trits removed
The paper (in case this was the cause)

On neat thing I did not realize is, if you flip this unit upside down, the display
also flips. Plus it comes with datalogger software for the computer. Not bad
for 150 bucks when most detectors using these same tubes are $400+.

I am not worried about the trits I carry in the slightest, but I wouldn't eat one either

they emit some beta which is mostly blocked by plastic, but loose trits close to a Geiger–Müller tube can be detected

Re: Geiger counters, radiation detectors, lets see 'em

Originally Posted by Illum

if you want to check the sensitivity of that monitor, buy some bananas
On the side note, I consider the aspect of monitoring radiation an exercise in futility... even if you know its presence, what could you do? Radiation contamination is very seldom regional, it "goes with the wind" per se. Knowing it and not knowing what to do after you know it is probably no better than not knowing.

what can you do ? make distance and move away from it.

it is not futility, it is understanding the environment that much better,
exactly what flashlights allow you to do. I buy a lot of weird items and travel
the globe quite a bit, and what I am actually afraid of is contaminated recycled metals,
because scrap metal thievery has become the non-drug way to get quick cash

every year, hundreds of devices containing radiation sources are lost, stolen, or otherwise
drop out of the system for tracking them. For example, a factory that has gone out of business
may contain one or more such devices. As the building structure is being dismantled, these
forgotten devices often are considered as scrap metal, or someone may think they have value and try to sell them.

here in Mass every state trooper has a super-sensitive detector in his/her trunk, there is not going to
be any stumbling into something radioactive in my safe little corner...but who knows
what goes on around the planet in 3rd worlds where rules don't really apply.

that, plus anything else I am no longer blind to...like darkness to the flashaholic, I am no longer blind

it is a fun toy, don't forget that. I am not that freaked out, if I was I'd have several $4000.00 units with
different types of probes and calibrated samples and whatnot...but hey Fukushima is a cold slap back to reality
that danger is everywhere... it is only a matter of 'time and mistakes and a catastrophe' to meet up at the
same time and place and.......this is an interesting toy.

Re: Geiger counters, radiation detectors, lets see 'em

Be advised that different radiation detectors are designed to detect different energies of radiation. Something that's good for alpha and beta won't be useful for gamma. Apart from that, I've forgotten all my training on the subject :S

Re: Geiger counters, radiation detectors, lets see 'em

i see people wandering how accurate a geigers counting to for the WTSHTF sinario..trust me, you dont need to see the number accuratly lolol!! it'll blow off the scale when them babies go off, after, waiting for that 'safe leval' is inthe millions of years, so when it bottoms at what ever number thats about the best you can hope fore.

long turm? ermmm too late lol. get as little as you can basically, in the 'bigger scale of things.

Re: Geiger counters, radiation detectors, lets see 'em

I was thinking about getting the watch mentioned on here...just for 'kicks' so to speak (I collect watches anyway). But as some one mentioned above...these detectors in practice would be, em difficult to use to use to any real effect I guess. I work in radiation physics, and we have to calibrate our instruments twice a day (day/night shift), and you also need counting efficiencies for accuracy. You need different instruments, or probes for alpha...then beta/gamma, and neutron separate.

Just think people may get worried, as we get high readings, low reading from day to day...background varies a lot with location, and after it rains etc (radon). Dont get me wrong, they maybe good, and from my gadget loving side I would get one :P but by the time you would pick up meaningful radiation readings, you would probably already be in trouble. Unless you are near 'sources' quite a lot?

Re: Geiger counters, radiation detectors, lets see 'em

Originally Posted by Illum

On the side note, I consider the aspect of monitoring radiation an exercise in futility... even if you know its presence, what could you do?

Manage your exposure. Many of the dangerous materials also have short half-lives. After a nuke event, you can hope to shelter in place (if you can get plenty of mass between you and outside), and after a couple of weeks it could be safe to go out again. Depending on how bad the radiation levels are, you might want to limit your outdoors time to 10 minutes, an hour, or whatever.

(For example, Iodine-131 has a half-life of about 8 days. Tellurium 129 has a half-life of 6 days.)

Re: Geiger counters, radiation detectors, lets see 'em

Originally Posted by CrazyIvan2011

I was thinking about getting the watch mentioned on here...just for 'kicks' so to speak (I collect watches anyway). But as some one mentioned above...these detectors in practice would be, em difficult to use to use to any real effect I guess. I work in radiation physics, and we have to calibrate our instruments twice a day (day/night shift), and you also need counting efficiencies for accuracy. You need different instruments, or probes for alpha...then beta/gamma, and neutron separate.

Just think people may get worried, as we get high readings, low reading from day to day...background varies a lot with location, and after it rains etc (radon). Dont get me wrong, they maybe good, and from my gadget loving side I would get one :P but by the time you would pick up meaningful radiation readings, you would probably already be in trouble. Unless you are near 'sources' quite a lot?

Saying that, some of our gear is...retro to say the least

Old thread....but I just got one of these (the new version) GCM-300E Plus V4
Pretty darn accurate little devices. I was able to determine the amount of radiation coming from my smoke detectors. One 50msv and one 62msv

Also, like someone else pointed out....you don't need exact, precise, scientific numbers.....just to know if there's an unusually high count. And you should put distance between you and that source.
Today, you have absolutely no idea what's in the truck next to you or where a source of radiation may be.

I like to throw it in a pocket and just carry it with me. It automatically alerts me if a preset level is reached. So far that hasn't happened but I do get occasional spikes.
I also check salmon and all seafood I get.

It was $100 delivered.
Another tool in the chest....like my L6 and other lights.

Re: Geiger counters, radiation detectors, lets see 'em

I considered getting one, But different radiation types require different detection tubes, so basically you want to detect the really deadly stuff, some radiation wont even penetrate your skin or clothing and the life of some radiation is very short.

I would check what type of meters Japan is using since Fukushima, though the general public might be getting sold the wrong type of meter, If this happened to China i would not buy any because of all the unscrupulous sellers, saving face over honesty.

John.

"Build a man a fire, and he'll be warm for a day. Set a man on fire, and he'll be warm for the rest of his life." - Terry Pratchett.

Re: Geiger counters, radiation detectors, lets see 'em

IMHO there is a lot to be said to possession of a Geiger counter, and preferably more than one.
More than one is desirable for a second opinion so as to avoid a false sense of security, or indeed a needless panic.

Most types are not terribly accurate, but that is not the idea, it is to give warning of levels significantly in excess of normal.

There is a lot that can be done if an abnormally high count is detected, even without any elaborate preps.
Firstly try and find out from media reports and your own observations if the problem is localised or regional.

If you sea or hear an explosion and the count rate trebles or worse, that suggests a terrorist attack or some form of fairly serious accident. Get someplace else URGENTLY. Even a few miles should help for a localised incident. In an urban area you might be able to simply take a bus or taxi away from danger if you act promptly before a few thousand others have the same idea.

For a regional event that can not be realistically escaped from, then shelter in place. Whilst construction standards vary a lot, as a VERY ROUGH GUIDE it may be said that being indoors in an inner room of a normal home reduces the dose to about one tenth of that received outside.
A domestic type of semi basement, or the inner parts of a modern office block reduce the dose to about one hundredth of that in the open.
A deep concrete basement of substantial construction, but NOT incorporating any specific radiation protective measures may reduce the dose to one thousandth of that received outside.
A purpose made shelter would give still better protection.

I have a couple of small and relatively cheap Geiger counters, "GEM RADALERT II" these are simple to use and give a simple bargraph display of coloured LEDs.
GREEN=NORMAL
YELLOW-PREPARE TO PANIC
RED=PANIC.

I purchased these new about 10? years ago. At the time these were issued to some members of the emergency services, and were selected for being simple and robust. The only control setting is a choice of averaging over 10 seconds, quicker if immediate danger is suspected, or 10 minutes which is much more accurate but you have to wait 10 minutes before getting a result.
These use a standard 9 volt battery and fit in a shirt pocket.
They detect the radiation from tritium lights if placed very close.

I also have a couple of larger and more sophisticated Geiger counters with a digital display, that can show dose rate per hour, or total dose per day/work shift, or simple number of counts. These operate silently OR with an audible "beep" for each count, and also have a programmable alarm that sounds when the dose rate or the total dose exceeds the programmed limit. These instruments require some knowledge of radiation physics to get best use. They also use standard 9 volt batteries and fit in a large coat or overall pocket.